Abstract text (incl. figure legends and references)
ONEM is a new hybrid microscopy technique in which an interface is probed by light in a non-invasive manner, and the structural information is read-out at high spatial resolution using electron optics. To achieve this, an ultra-thin photocathode layer is inserted in the near-field region right after the sample [2], and emitted photo-electrons are collected by the objective lens of an aberration-corrected low-energy electron microscope (LEEM) [3]. The potential applications for ONEM is in life sciences and electrochemical studies.
Electrochemistry studies the processes that occur on the interface of electrodes and electrolytes due to the flow of electrons or ions. This field of study has found widespread applications in nanomanufacturing, developing batteries, hydrogen-based fuels, biosensors and etc [1]. Therefore, measuring the local changes in the formed structures over the whole area of the electrode-electrolyte interface is of great importance.
Despite the significant advances in the development of optical super-resolution and electron microscopes, real-time, damage and label free imaging of dynamics in nm-resolution is yet not achieved. Here, we introduce optical near-field electron microscopy (ONEM) as a noble technique to study electrochemical processes in real time with a few nanometers of spatial resolution. ONEM will be benchmarked with other state of art techniques such as interferometric scattering microscopy (iSCAT) and liquid cell electron microscopy (LC-EM).
ONEM is an ongoing project in collaboration with the Leiden University, Czech academy of sciences, and the Univerity of Vienna.
References:
[1] Beker, Anne France, et al. "In situ electrochemistry inside a TEM with controlled mass transport." Nanoscale 12.43 (2020): 22192-22201.
[2] Marchand, Raphaël, et al. "Optical near-field electron microscopy." Physical Review Applied 16.1 (2021): 014008.
[3] Geelen, D., et al. "Nonuniversal transverse electron mean free path through few-layer graphene." Physical review letters 123.8 (2019): 086802.